you may have a couple problems happening at the same time. your speedo has to do with the speed sensor located in the diff. There is a plug attached to the cover - check the wiring for corrosion.
the gas and temp gauges could be either the small nuts have loosened on the back of the cluster and or possibly the batteries in the circuit board are going bad.
the blinkers could be bulb related or relay related - that is located under the dash near the steering column.
you may want to try google; it's a good thing. :-) do a search there.